Step-by-step explanation:
Mohs scale is a scale that represents hardness of different minerals in increasing order from bottom to top.
So, according to Mohs scale hardness of given minerals is rated as follows.
Apaptite is at number 5.
Calcite is at number 3.
Corundum is at number 9.
Feldspar is at number 6.
Talc is at number 1.
Therefore, given minerals in order of decreasing hardness are listed as follows.
Corundum > Feldspar > Apaptite > Calcite > Talc